The PowerPC 7450/7455 processor does not support frequency scaling, so there is no need to activate this feature. Additionally all stock processors don't feature temperature sensors, but it may well be that third party upgrades do.

wandering what does it means .... "additionally all stock processors don't feature temperature sensors, but it may well be that third party upgrades do" ??

"but it may well be that third party upgrades do" ???? isn't there a way in the kernel to read the core temperature ?

192 config TAU
193 bool "On-chip CPU temperature sensor support"
194 depends on 6xx
195 help
196 G3 and G4 processors have an on-chip temperature sensor called the
197 'Thermal Assist Unit (TAU)', which, in theory, can measure the on-die
198 temperature within 2-4 degrees Celsius. This option shows the current
199 on-die temperature in /proc/cpuinfo if the cpu supports it.
200
201 Unfortunately, on some chip revisions, this sensor is very inaccurate
202 and in many cases, does not work at all, so don't assume the cpu
203 temp is actually what /proc/cpuinfo says it is.

about kernel 2.6.32 ... /proc/cpuinfo is not reporting the core temp

so anybody know a pretty way to get the core temp value for the userland (or a patch/hack/some kind of voodoo magic ) ?

*
* The G4 "windtunnel" has a single fan controlled by an
* ADM1030 fan controller and a DS1775 thermostat.
*
* The fan controller is equipped with a temperature sensor
* which measures the case temperature. The DS1775 sensor
* measures the CPU temperature. This driver tunes the
* behavior of the fan. It is based upon empirical observations
* of the 'AppleFan' driver under Mac OS X.
*
* WARNING: This driver has only been testen on Apple's
* 1.25 MHz Dual G4 (March 03). It is tuned for a CPU
* temperature around 57 C.
*